/*
silverPDF is sponsored by Aleyant Systems (http://www.aleyant.com)

silverPDF is based on PdfSharp (http://www.pdfsharp.net) and iTextSharp (http://itextsharp.sourceforge.net)

Developers: Ai_boy (aka Oleksii Okhrymenko)

Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation
files (the "Software"), to deal in the Software without
restriction, including without limitation the rights to use,
copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following
conditions:

The above information and this permission notice shall be
included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR SPONSORS
BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.

*/
#region PDFsharp - A .NET library for processing PDF
//
// Authors:
//   Stefan Lange (mailto:Stefan.Lange@pdfsharp.com)
//
// Copyright (c) 2005-2008 empira Software GmbH, Cologne (Germany)
//
// http://www.pdfsharp.com
// http://sourceforge.net/projects/pdfsharp
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
// DEALINGS IN THE SOFTWARE.
#endregion

using System;
using System.Diagnostics;
using System.Collections;
using System.Collections.Generic;
using System.Text;
using System.IO;
using PdfSharp.Drawing;
using PdfSharp.Internal;
using PdfSharp.Fonts;
using PdfSharp.Fonts.TrueType;
using PdfSharp.Pdf.Advanced;
using PdfSharp.Pdf.Filters;

namespace PdfSharp.Pdf.Advanced
{
  /// <summary>
  /// Represents a ToUnicode map for composite font.
  /// </summary>
  internal sealed class PdfToUnicodeMap : PdfDictionary
  {
    public PdfToUnicodeMap(PdfDocument document)
      : base(document)
    {
    }

    public PdfToUnicodeMap(PdfDocument document, CMapInfo cmapInfo)
      : base(document)
    {
      this.cmapInfo = cmapInfo;
    }

    /// <summary>
    /// Gets or sets the CMap info.
    /// </summary>
    public CMapInfo CMapInfo
    {
      get { return this.cmapInfo; }
      set { this.cmapInfo = value; }
    }
    CMapInfo cmapInfo;

    /// <summary>
    /// Creates the ToUnicode map from the CMapInfo.
    /// </summary>
    internal override void PrepareForSave()
    {
      base.PrepareForSave();

      // This code comes literaly from PDF Reference
      string prefix =
        "/CIDInit /ProcSet findresource begin\n" +
        "12 dict begin\n" +
        "begincmap\n" +
        "/CIDSystemInfo << /Registry (Adobe)/Ordering (UCS)/Supplement 0>> def\n" +
        "/CMapName /Adobe-Identity-UCS def /CMapType 2 def\n";
      string suffix = "endcmap CMapName currentdict /CMap defineresource pop end end";

      Hastable glyphIndexToCharacter = new Hastable();
      int lowIndex = 65536, hiIndex = -1;
      foreach (KeyValuePair<char, int> entry in this.cmapInfo.CharacterToGlyphIndex)
      {
        int index = (int)entry.Value;
        lowIndex = Math.Min(lowIndex, index);
        hiIndex = Math.Max(hiIndex, index);
        //glyphIndexToCharacter.Add(index, entry.Key);
        glyphIndexToCharacter[index] = entry.Key;
      }

      MemoryStream ms = new MemoryStream();
      StreamWriter wrt = new StreamWriter(ms, new ASCIIEncoding());

      wrt.Write(prefix);

      wrt.WriteLine("1 begincodespacerange");
      wrt.WriteLine(String.Format("<{0:X4}><{1:X4}>", lowIndex, hiIndex));
      wrt.WriteLine("endcodespacerange");

      // Sorting seems not necessary. The limit is 100 entries, we will see.
      wrt.WriteLine(String.Format("{0} beginbfrange", glyphIndexToCharacter.Count));
      foreach (KeyValuePair<object, object> entry in glyphIndexToCharacter)
        wrt.WriteLine(String.Format("<{0:X4}><{0:X4}><{1:X4}>", (int)entry.Key, (int)(char)entry.Value));
      wrt.WriteLine("endbfrange");

      wrt.Write(suffix);
      wrt.Close();

      // Compress like content streams
      byte[] bytes = ms.ToArray();
      ms.Close();
      if (Owner.Options.CompressContentStreams)
      {
        Elements.SetName("/Filter", "/FlateDecode");
        bytes = Filtering.FlateDecode.Encode(bytes);
      }
      PdfStream stream = CreateStream(bytes);
    }

    public sealed class Keys : PdfDictionary.PdfStream.Keys
    {
    }
  }
}
